What exactly makes white cell boosters (like Neulasta) be so painful?


My mom handled chemo and surgery more or less ok, but the only time I saw her cry and scream in pain was with Neulasta shots. The doctor just said her bone marrow was being stimulated but I don’t understand why that stimulation results in unbearable pain.

In: 4

My sister had them. It stimulates the bone marrow to expand and that expansion is felt by the nerves.

White blood cells are mainly produced inside the bones. In the bone marrow specifically.

For this example, think of your bones as hollow tubes, filled with some structural elements, but mainly bone marrow.

The drugs that promote white cell synthesis (production), increase the amount of activity in the bone marrow, causing it to swell up. Now as there is not much space for it to actually expand, it increases in pressure and literally pushes on your bones from the inside.

This can be extremely painful.